Ag/Cu(001): Observation of the development of the electronic structure in metal overlayers from two to three dimensionality

Angle-resolved photoemission was used to investigate the valence-band structure of the metal overlayer system c(10×2)Ag/Cu(001). At 1-2-monolayer coverages, the Ag adlayer exhibited d-band spectral behavior characteristic of two-dimensional dispersion. Evaporation of progressively more Ag onto the substrate produced a series of surfaces which by 3-5-monolayer exposures were converging toward a three-dimensional valence electronic structure characteristic of a bulk, Ag(111)-like system.